Offprint means a separate reprint of an article or chapter that has previously been published. The antonyms for this word would be "original," "first edition," or "initial publication." These terms refer to the original publication of an article, rather than a separate reprint. Synonyms for offprint include "reprint," "republication," and "afterprint," which all refer to a subsequent printing of an already-existing work. Using antonyms and synonyms can help to clarify meaning and avoid repetition in writing. It is important to understand the various nuances and connotations that these words carry in order to use them correctly and effectively in writing.